Safe Haskell	Safe-Infered

Network.Wai.Middleware.Cache.Redis

Contents

Cache backend
Helpers

Description

Redis backend for Network.Wai.Middleware.Cache.

This backend uses Database.Redis.Pile for low-lewel operations.

 cache
     (redisBackend 
         -- use defaults, DB 0 and "myprefix" 
         R.defaultConnectInfo 0 "myprefix"
         (const Nothing)    -- no expiration
         (const ["mytag"])  -- simply one tag "mytag"
         (rawPathInfo)      -- URL path as key 
         lookupETag         -- And find "If-None-Match"
     ) app -- our app

Synopsis

Cache backend

redisBackend Source

Arguments

:: ConnectInfo	Redis connection info.
-> Integer	Redis DB.
-> ByteString	Cache prefix for key and tags. See Database.Redis.Pile for details.
-> (Request -> Maybe Integer)	TTL extraction. Use `Nothing` for no expiration.
-> (Request -> [ByteString])	Tags extraction. See Database.Redis.Pile for details.
-> (Request -> ByteString)	Key extraction.
-> (Request -> Maybe ByteString)	`ETag` value extraction. To extract `If-None-Match` header use `lookupETag`. Use `(const Nothing)` for block `304`-responses.
-> CacheBackend

Redis backend for Network.Wai.Middleware.Cache.

Except caching, this backend always adds ETag to Response headers with hexed SHA1 as value.

This backend can't cache files. Use routing or catch CacheBackendError

Helpers

lookupETag :: Request -> Maybe ByteString Source

Helper for extract If-None-Match header from Request.